1. Field
This disclosure relates generally to switched capacitor circuits, and more specifically, to a gain enhanced switched capacitor circuit.
2. Related Art
Switched capacitor circuits are commonly used in mixed signal circuitry, such as to form buffers, gain stages, integrators, etc. For example, a switched capacitor circuit is commonly used within a sample and hold circuit. One type of switched capacitor circuit available today is a gain enhanced switched capacitor circuit. In such a gain enhanced switched capacitor circuit, the input is sampled with respect to virtual ground of a closed loops amplifier; however, an inverting configuration (which results in a negative integration) in the sampling phase is utilized. This negative integration causes the output of the circuit to move in the opposite direction to what is desired. This, in turn, increases the slew rate requirement of the operational amplifier during transition from the sampling phase to the holding phase, which limits the speed of the circuit. Therefore, a need exists for an improved gain enhanced switched capacitor circuit.